Some Egyptian imam says sex with captives is permitted and is indeed beneficial to the captive because it fosters warm feelings and attachment between owner and captive. Allah is merciful and Allah knows best.
The canonical Islamic Laws and scripture consists of Koran, Suna and Hadith. Bukhari would be the Hadith in this case. Let me quote from Ali Sina's book. It should be noted that Muhammad was considered the perfect man, the perfect example of behavior and it was stipulated that the laws of Islam are unchangeable. Muslims are stuck with this.
From Ali Sina's book "Understanding Muhammad". p. 39 Rape
Muhammad allowed his men to rape the women captured in raids. However Muslims faced a dilemma. They wanted to have sex with their female captives, but also wanted to return them for ransom and therefore did not want to make them pregnant. Some of these women were already married whose husbands had escaped when taken by surprise and were still alive. The raiders considered the possibility of "coitus interruptus" (withdrawing from intercourse before ejaculation). Unsure of the best course of action, they sought the counsel of their Prophet. Buhkari reports:
Abu Saeed said "We went out with Allah's Apostle for the Ghazwa of Banu Al-Mustaliq and we received captives from among the Arab captives and we desired women and celibacy became hard on us and we loved to do coitus interruptus. So when we intended to do coitus interruptus, we said "How can we do coitus interruptus before asking Allah's Apostle who is present among us?" We asked (him) about it and he said "It is better for you not to do so, for if any soul (till the Day of Resurrection) is predestined to exists, it will exist.
Bukhari, Volume 5, Book 59, Number 459.
Muhammed did not forbid raping the captive women. Instead he made an asinine claim that when Allah intends to create someone, nothing can prevent it. He told his men that coitus interruptus is ill-advised because it would be an attempt to thwart the will of Allah. He did not say a word against the rape of the captives, and by discouraging coitus interruptus, he supported forced insemination.
He made even his god to legitimize intercourse with women captured in wars, the so-called "right hand possessions," even if they were married before their capture.
The subhuman treatment of non-Muslim women by jihadi organizations such as the Islamic State or Nigeria's Boko Haram - where "infidel women are bought, sold, gang-raped, mutilated, dismembered and burned alive - is relatively well known (thanks to ISIS itself, for disseminating images and videos). Less well known is that "infidel" women are treated in similar ways all across the Muslim world, as explained by a 2016 report:
from: Violent Sexual Obsession and Rape as Expression of Islamic Spirituality
by Skeptic Infidel, posted at Islam Watch, 19 Mar. 2009
Islam’s scriptural authorities require faithful Muslim’s to “humiliate” non-believers, and to bring them to an understanding of their state of degradation. The humiliation and degradation of women has become, despite Islam’s denials, an extension of this spiritual directive, with sexuality being the tool for the expression of Islamic dominance, as well as a weapon with which to punish the disobedient and the unbelieving.
Muslim male supremacy requires all women to submit, including women within non-believing countries, and as noted specifically within the Koran AND Shari’a law, there is no such thing as the rape of an unbelieving female, as such intercourse, forcible or otherwise, was approved by Mohammed as an absolute right of entitlement of Muslim men, as specifically addressed by the Koran in 4:24.
...
It is within this cultural dynamic that is to be found the source of the gross overkill and sexual torture that has become the common and consistently characteristic signature of Muslim violence toward their non-Muslim and apostate captives.
On September 1, 2004, in the Russian Federation town of Beslan, Muslim terrorists descended upon a school, taking more than 1,100 people hostage, including nearly 800 school children.
Over the next several days Russian security forces attempted to negotiate a peaceful resolution, ultimately failing, with the resultant carnage of the deaths of 334 hostages of which 186 were children. Nearly all the survivors were in some manner wounded, if not emotionally scared for a lifetime.
On November 26, 2008, in Mumbai, India, Muslim terrorists simultaneously undertook coordinated attacks upon as many as eight separate targets, and over the next two days fought pitched battles with police and security forces, eventually resulting in the deaths of at least 173 and injuries to more than 300 additional people.
In each instance, immediately upon seizing a target and establishing a defensible perimeter, some portion or room of the seized building, was established, solely for the purpose of pursuing a large scale assembly line process of rape, sodomy, sexual torture and mutilation, and seemingly as an after act, the ritual beheading of captives.
Immediately upon seizure, and while in the process of ongoing negotiation with Russian security forces, those within selected from among their captives, those who would be sexually violated and abused; they were in their regard as captors, equal opportunity violators, with men, women, boys and girls, each in their turn grossly violated, sexually mutilated, and as an after act, killed.
More than 100 were children.